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This work was aimed at evaluating the cardioprotective effects of Castanea sativa Mill. (CSM) bark extract characterized in its phenolic composition by HPLC-DAD-MS analysis. The study was performed using primary cultures of neonatal rat cardiomyocytes to investigate the antioxidant and cytoprotective effects of CSM bark extract and isolated guinea pig left and right atria, left papillary muscle, and aorta to evaluate its direct effect on cholinergic and adrenergic response. In cultured cardiomyocytes the CSM bark extract reduced intracellular reactive oxygen species formation and improved cell viability following oxidative stress in dose-dependent manner. Moreover, the extract decreased the contraction induced by noradrenaline (1  μ M) in guinea pig aortic strips and induced transient negative chronotropic and positive inotropic effects without involvement of cholinergic or adrenergic receptors in the guinea pig atria. Our results indicate that CSM bark extract exhibits antioxidant activity and might induce cardioprotective effect.

A wide variety of acute and chronic neurodegenerative diseases, including ischemic/traumatic brain injury, Alzheimer's disease, and Parkinson's disease, share common characteristics such as oxidative stress, misfolded proteins, excitotoxicity, inflammation, and neuronal loss. As no drugs are available to prevent the progression of these neurological disorders, intervention strategies using phytochemicals have been proposed as an alternative form of treatment. Among phytochemicals, isothiocyanate sulforaphane, derived from the hydrolysis of the glucosinolate glucoraphanin mainly present in Brassica vegetables, has demonstrated neuroprotective effects in several in vitro and in vivo studies. In particular, evidence suggests that sulforaphane beneficial effects could be mainly ascribed to its peculiar ability to activate the Nrf2/ARE pathway. Therefore, sulforaphane appears to be a promising compound with neuroprotective properties that may play an important role in preventing neurodegeneration.

The term cardiorenal syndrome (CRS) refers to multiple possible clinicopathological correlations between heart and kidney failure. The most recent classification recognizes five types of CRS: types I and II originate from heart failure (acute and chronic, respectively), type III and IV from kidney failure (again acute and chronic), while type V originates from a range of systemic diseases. Echocardiography and renal ultrasound are important means to arrive at a correct diagnosis. Basic echocardiography (defined by some as "echocardioscopy") allows the assessment of the left and right ventricles (diastolic and systolic function), atrial size, pulmonary circulation markers such as systolic pulmonary arterial pressure (PAPs) and tricuspid annular plane excursion (TAPSE), pericardial effusions, valve dysfunctions, and volume repletion. Renal ultrasound is of help in distinguishing between chronic and acute renal failure (kidney volume, parenchymal thickness, echogenicity) and excluding obstructive kidney disease.

INTRODUCTION: Chronic kidney disease (CKD) is a widespread invalidating condition, leading to erythropoietin deficiency and decreased cardiovascular performance. Darbepoetin-α and epoetin-α are extensively used to correct renal anemia. The aim of this study was to evaluate cardiological outcomes in two groups of CKD patients treated with erythropoiesis-stimulating agents (ESA: 20 μg darbepoetin-α weekly vs. 2,000 IU epoetin-α thrice weekly) with an unconventional 1:300 conversion ratio. METHODS: The study was designed as a single center, retrospective, observational study. One hundred stage IV CKD patients were selected. Hemoglobin (Hb), hematocrit, C-reactive protein, pro-brain natriuretic peptide (BNP) and basal echocardiograms were monitored every 3 months. RESULTS: Darbepoetin-α was significantly more effective in increasing Hb levels after 3 (p < 0.0001), 6 (p < 0.0001), 9 (p < 0.01) and 12 months (p < 0.01) compared to epoetin-α. The optimal Hb target level (11 g/dl < Hb < 12 g/dl) was completely reached after 1 year of treatment with darbepoetin-α and in 70% of the patients treated with epoetin-α (p < 0.01). Cardiovascular performance (left ventricular end-diastolic volume, ejection fraction and pro-BNP) was significantly improved after darbepoetin-α treatment at the 6- and 12-month follow-ups compared to epoetin-α. Discussion: Despite the limitations of a retrospective observational study, these results encourage nephrologists to test the 1:300 darbepoetin/epoetin conversion ratio in 'easy' patients, and aggressive protocols for the treatment of anemia in CKD patients are avoided. Darbepoetin-α appeared effective in anemia correction, improving cardiovascular performance in a significantly higher proportion than epoetin. At low doses, on the other hand, it has to be borne in mind that a treatment regimen with only one submaximal administration per week may increase patient compliance and adherence to therapy, explaining in part the observed results.

The term cardiorenal syndrome (CRS) describes a broad spectrum of clinical conditions with four combinations of acute and chronic heart and kidney failure. Based on the pathophysiological primum movens, the actual classification recognizes five CRS types: in type I and II CRS, the initiating event is heart failure (acute or chronic), while it is kidney failure in type III and IV CRS; type V is linked to systemic diseases. Ultrasound techniques (echocardiography and ultrasonography of the kidney, inferior vena cava and chest) can be extremely helpful in establishing a prompt diagnosis and a correct CRS classification. Basic echocardiography allows evaluation of ventricular diastolic and systolic functions, investigates pulmonary congestion and pericardial effusion, and describes volume overload. On the other hand, renal ultrasound helps clinicians to distinguish between acute and chronic renal failure, excludes urinary tract dilation or pathological bladder repletion, and provides crucial information regarding kidney volume or echogenicity. Applying basic knowledge of echocardiography and renal ultrasound, nephrologists may be in a better position for patient treatment and management, bearing in mind that doctors can properly use a stethoscope although not being a cardiologist.

Among health-promoting phytochemicals in whole grains, phenolic compounds have gained attention as they have strong antioxidant properties and can protect against many degenerative diseases. Aim of this study was to profile grain phenolic extracts of one modern and five old common wheat (Triticum aestivum L.) varieties and to evaluate their potential antiproliferative or cytoprotective effect in different cell culture systems.Wheat extracts were characterized in terms of antioxidant activity and phenolic composition (HPLC/ESI-TOF-MS profile, polyphenol and flavonoid contents). Results showed that antioxidant activity (FRAP and DPPH) is mostly influenced by flavonoid (both bound and free) content and by the ratio flavonoids/polyphenols. Using a leukemic cell line, HL60, and primary cultures of neonatal rat cardiomyocytes, the potential antiproliferative or cytoprotective effects of different wheat genotypes were evaluated in terms of intracellular reactive oxygen species levels and cell viability. All tested wheat phenolic extracts exerted dose-dependent cytoprotective and antiproliferative effects on cardiomyocytes and HL60 cells, respectively. Due to the peculiar phenolic pattern of each wheat variety, a significant genotype effect was highlighted. On the whole, the most relevant scavenging effect was found for the old variety Verna. No significant differences in terms of anti-proliferative activities among wheat genotypes was observed.Results reported in this study evidenced a correspondence between the in vitro antioxidant activity and potential healthy properties of different extracts. This suggests that an increased intake of wheat grain derived products could represent an effective strategy to achieve both chemoprevention and protection against oxidative stress related diseases.

The isothiocyanate sulforaphane (SF), abundant in Cruciferous vegetables, is known to induce antioxidant/detoxification enzymes in many cancer cell lines, but studies focused on its cytoprotective action in nontransformed cells are just at the beginning. Since we previously demonstrated that SF elicits cardioprotection through an indirect antioxidative mechanism, the aim of this study was to analyze the signaling pathways through which SF exerts its protective effects. Using cultured rat cardiomyocytes, we investigated the ability of SF to activate Akt/protein kinase B (PKB) and extracellular signal-regulated kinase 1 and 2 (ERK1/2) signaling pathways, which are implicated in cardiac cell survival, and to increase the phosphorylation of Nuclear factor E2-related factor 2 (Nrf2) and its binding to the antioxidant response element. By means of specific inhibitors, we demonstrated that the Phosphatidylinositol 3-kinase (PI3K)/Akt pathway represents a mechanism through which SF influences both expression and activity of glutathione reductase, glutathione-S-transferase, thioredoxin reductase, and NAD(P)H:quinone oxidoreductase-1, analyzed by western immunoblotting and spectrophotometric assay, respectively, and modulates Nrf2 binding and phosphorylation resulting in a cytoprotective action against oxidative damage. Results of this study confirm the importance of phase II enzymes modulation as cytoprotective mechanism and support the nutritional assumption of Cruciferous vegetables as source of nutraceutical cardioprotective agents., (© 2011 Institute of Food Technologists®)

Oxidative damage plays an important role in the pathogenesis of colorectal (CR) cancer. This study investigated the activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione-S-transferase (GST) in plasma of 82 participants of a screening program for CR cancer prevention (30 females and 52 males; age 50-70 years). All subjects resulted positive to fecal occult blood test and were subsequently classified, according to the colonoscopy and histological findings, in patients with CR cancer, patients with colorectal polyps or controls. Furthermore, the activity of clastogenic factors (CFs) in plasma from study population was measured as the ability of inducing micronuclei (MN) in vitro in peripheral of a healthy donor. CAT and GR activities were significantly lower in CR cancer patients compared to controls (P<0.05) and polyps groups (P<0.05). SOD activity was significantly higher in patients with CR cancer than in polyp (P<0.05) and control (P<0.05) groups. GST activity was not significantly different in plasma of the three groups. An increase of CFs induction was observed in plasma of CR cancer patients (MN: 8.89±3.42) with respect to control (MN: 6.37±0.96 P<0.05). These results can contribute to define plasma biomarkers associated to oxidative stress damage that could predictive of CR cancer risk., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Ischemic preconditioning is a complex cardioprotective phenomenon that involves adaptive changes in cells and molecules and occurs in a biphasic pattern: an early phase after 1-2 h and a late phase after 12-24 h. While it is widely accepted that reactive oxygen species are strongly involved in triggering ischemic preconditiong, it is not clear if they play a major role in the early or late phase of preconditioning and which are the mechanisms involved. The present study was designed to investigate the mechanisms behind H(2)O(2)-induced cardioprotection in rat neonatal cardiomyocytes. We focused on antioxidant and phase II enzymes and their modulation by protein kinase signaling pathways and nuclear-factor-E(2)-related factor-1 (Nrf1) and Nrf2. H(2)O(2) preconditioning was able to counteract oxidative stress more effectively in the late than in the early phase of adaptation. In particular, H(2)O(2) preconditioning counteracted oxidative stress-induced apoptosis by decreasing caspase-3 activity, increasing Bcl2 expression and selectively increasing the expression and activity of antioxidant and phase II enzymes through Nrf1 and Nrf2 translocation to the nucleus. The downregulation of Nrf1 and Nrf2 by small interfering RNA reduced the expression level of phase II enzymes. Specific inhibitors of phosphatidylinositol 3-kinase/Akt and p38 MAPK activation partially reduced the cardioprotection elicited by H(2)O(2) preconditioning and the induction and activity of phase II enzymes. These findings demonstrate, for the first time, a key role for Nrf1, and not only for Nrf2, in the induction of phase II enzymes triggered by H(2)O(2) preconditioning.

There is an increasing awareness that astrocytes, the most abundant cell type in the central nervous system, are critical mediators of brain homeostasis, playing multifunctional roles including buffering potassium ions, maintaining the blood-brain barrier, releasing growth factors, and regulating neurotransmitter levels. Defects in astrocyte function have been implicated in a variety of diseases including age-related diseases such Alzheimer's disease and Parkinson's disease. However, little is known about the age-related changes that occur in astrocytes and if these cells are able to generate a senescent phenotype in response to stress. In this report we have examined whether astrocytes can initiate a senescence program similar to that described in other cell types in response to a variety of stresses. Our results indicate that after oxidative stress, proteasome inhibition, or exhausted replication, human and mouse astrocytes show changes in several established markers of cellular senescence. Astrocytes appear to be more sensitive to oxidative stress than fibroblasts, suggesting that stress-induced senescence may be more pronounced in the brain than in other tissues., (Copyright © 2010 Elsevier Inc. All rights reserved.)

A reduction in IGF-I signaling has been found to increase lifespan in multiple organisms despite the fact that IGF-I is a trophic factor for many cell types and has been found to have protective effects against multiple forms of damage in acute settings. The increase in longevity seen in response to reduced IGF-I signaling suggests that there may be differences between the acute and chronic impact of IGF-I signaling. We have examined the possibility that long-term stimulation with IGF-I may have a negative impact at the cellular level using quiescent human fibroblasts. We find that fibroblast cells exposed to IGF-I for 14 days have reduced long-term viability as judged by colony forming assays, which is accompanied by an accumulation of senescent cells. In addition we observe an accumulation of cells with depolarized mitochondria and a reduction in autophagy in the long-term IGF-I treated cultures. An examination of mice with reduced IGF-I levels reveals evidence of enhanced autophagy and fibroblast cells derived from these mice have a larger mitochondrial mass relative to controls indicating that changes in mitochondrial turnover occurs in animals with reduced IGF-I. The results indicate that chronic IGF-I stimulation leads to mitochondrial dysfunction and reduced cell viability.

Sulforaphane (SF), one of the most important isothiocyanates in the human diet, present in cruciferous vegetables, is known to have chemopreventive activities in different tissues. No data are available on its effects in the prevention of skeletal muscle damage. In this study, we investigated the potential protective effects of SF treatment on muscle damage and oxidative stress induced by an acute bout of exhaustive exercise in rats. Male Wistar rats were treated with SF (25 mg/kg body wt ip) for 3 days before undergoing an acute exhaustive exercise protocol in a treadmill (+7% slope and 24 m/min). Acute exercise resulted in a significant increase in plasma lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) activities. It also resulted in a significant increase in thiobarbituric acid-reactive substances, in a significant decrease in tissue total antioxidant capacity, and in a significant decrease in NAD(P)H:quinone oxidoreductase 1 (NQO1) expression and activity in vastus lateralis muscle. SF treatment significantly increased muscle NQO1, glutathione-S-transferase, and glutathione reductase expression and activity, with no effect on glutathione peroxidase and thioredoxin reductase. The observed SF-induced upregulation of phase II enzymes was accompanied by a significant increase in nuclear erythroid 2 p45-related factor 2 expression and correlated with a significant increase in total antioxidant capacity and a decrease in plasma LDH and CPK activities. Our data demonstrate that SF acts as an indirect antioxidant in skeletal muscle and could play a critical role in the modulation of the muscle redox environment, leading to the prevention of exhaustive exercise-induced muscle damage.

Oxidative stress plays a major role in the pathophysiology of cardiac disorders, but the experimental data on the protective effects of exogenous antioxidants are controversial. A promising cardioprotective strategy may be through the induction of the endogenous antioxidants and phase II enzymes by chemical inducers. Sulforaphane is an isothiocyanate derived from cruciferous vegetables, and it has gained attention mainly as a potential chemopreventive agent in part through the induction of detoxifying enzymes. Accordingly, this study was undertaken to investigate the time-dependent induction of gene transcription, protein expression, and enzyme activity of antioxidant and phase II enzymes [glutathione reductase, glutathione-S-transferase, glutathione peroxidase, NAD(P)H:quinone oxidoreductase-1, thioredoxin reductase] by sulforaphane in cultured rat neonatal cardiomyocytes. The potential cardioprotective action of sulforaphane was confirmed by the decrease in intracellular reactive oxygen species production, the increase in cell viability, and the decrease in DNA fragmentation after long-term treatment accompanied by the induction of antioxidants and phase II enzymes in cardiomyocytes.

Exposure to indoor allergens is an important risk factor for sensitisation and respiratory allergy. The aim of this paper was to evaluate the levels of mite, cat and latex allergens in dust collected from an indoor workplace and to assess whether the exposure to these allergens was associated with the allergy symptoms reported by employees. Sixty dust samples were collected. Allergen concentrations were measured with antibody based ELISAs. All 144 participants compiled a questionnaire exploring possible symptoms of allergy. No association between latex allergen exposure and symptoms was found in spite of the high frequency of latex allergens. Mite allergens were detected in a minority of rooms. Cat allergen was the most important indoor allergen in the sampled workplace and exposure to this allergen could represent a risk for employees.

Objective: Recent evidence in animal models suggests that components of the extracellular matrix (ECM) play a primary role in peripheral nerve degeneration and regeneration., Methods: We investigated the expression of several ECM molecules in human sural nerves by immunohistochemistry, Western blot, and reverse transcriptase PCR analysis. To unravel the possible role of these molecules in nerve regeneration, we compared results obtained from nerves with abundant signs of regeneration with those with complete absence of axonal regeneration. The role of some ECM components on neurite extension was further tested in dorsal root ganglion cultures., Results: We observed that the ECM composition significantly differs in regenerating compared with nonregenerating nerves, independently from their etiologic background. Fibronectin was abundantly expressed in regenerating nerves, whereas vitronectin and fibrin(ogen) prevailed in nonregenerating nerves. Whereas fibronectin is secreted by endoneurial cells, in vivo and vitro studies showed that the source of vitronectin and fibrin(ogen) is the bloodstream., Conclusions: These data indicate that nerve regeneration is impaired in the presence of breaches in the blood-nerve barrier or impaired extracellular matrix (ECM) degradation that leads to accumulation of plasma vitronectin and fibrin(ogen). The transformation into mature, fibronectin-enriched ECM is necessary for efficient nerve regeneration in humans.

The authors evaluated the role of a high-protein, low-calorie, polyunsaturated fatty-acid (PUFA) -supplemented diet on anthropometric parameters, erythrocyte-membrane fatty-acid composition, and plasma antioxidant defenses of nonprofessional volleyball athletes. The athletes were divided in two groups: One (n = 5) followed the Mediterranean diet, and the other (n = 6) followed a high-protein, low-calorie diet with a 3-g/day fish-oil supplementation. All the athletes had anthropometric measurements taken, both at the beginning and at the end of the study, which lasted for 2 months. Body-mass index and total body fat were significantly diminished in the second group, while they remained unchanged in the first. Plasma total antioxidant activity (TAA) was significantly increased in the plasma of both groups, with no differences between the groups, suggesting that physical activity, not the different diets, is the main contributor to the increase of plasma TAA. The second group showed a significant increase in erythrocyte-membrane PUFA content and in the unsaturation index value (UI) because of the fish-oil supplementation.A high-protein, low-carbohydrate, fish-oil-supplemented diet seems to be useful only when the aim of the diet is to obtain weight loss in a short-term period. The significant increase in the UI of erythrocyte membranes indicates the potential for harm, because a high intake of PUFA might increase susceptibility to lipid peroxidation not counterbalanced by a higher increase in TAA. Adherence to the Mediterranean diet seems to be the better choice.

An original analytical method has been developed for the determination of the antioxidants trans-resveratrol (t-RSV) and cis-resveratrol (c-RSV) and of melatonin (MLT) in red and white wine. The method is based on HPLC coupled to fluorescence detection. Separation was obtained by using a RP column (C8, 150 mm x 4.6 mm id, 5 mum) and a mobile phase composed of 79% aqueous phosphate buffer at pH 3.0 and 21% ACN. Fluorescence intensity was monitored at lambda = 386 nm while exciting at lambda = 298 nm, mirtazapine was used as the internal standard. A careful pretreatment of wine samples was developed, using SPE with C18 cartridges (100 mg, 1 mL). The calibration curves were linear over the following concentration ranges: 0.03-5.00 ng/mL for MLT, 3-500 ng/mL for t-RSV and 1-150 ng/mL for c-RSV. The LOD values were 0.01 ng/mL for MLT, 1 ng/mL for t-RSV and 0.3 ng/mL for c-RSV. Precision data, as well as extraction yield and sample purification results, were satisfactory. Thus, the method seems to be suitable for the analysis of MLT and resveratrol isomers in wine samples. Moreover, wine total polyphenol content and antioxidant activity were evaluated.

The mitochondrial metalloprotease AFG3L2 assembles with the homologous protein paraplegin to form a supracomplex in charge of the essential protein quality control within mitochondria. Mutations of paraplegin cause a specific axonal degeneration of the upper motoneuron and, therefore, hereditary spastic paraplegia. Here we present two Afg3l2 murine models: a newly developed null and a spontaneous mutant that we found carrier of a missense mutation. Contrasting with the mild and late onset axonal degeneration of paraplegin-deficient mouse, Afg3l2 models display a marked impairment of axonal development with delayed myelination and poor axonal radial growth leading to lethality at P16. The increased severity of the Afg3l2 mutants is explained by two main molecular features that differentiate AFG3L2 from paraplegin: its higher neuronal expression and its versatile ability to support both hetero-oligomerization and homo-oligomerization. Our data assign to AFG3L2 a crucial role by linking mitochondrial metabolism and axonal development. Moreover, we propose AFG3L2 as an excellent candidate for motoneuron and cerebellar diseases with early onset unknown etiology.

Despite extensive studies, the fundamental mechanisms responsible for the development and progression of cardiovascular diseases have not yet been fully elucidated. Recent experimental and clinical studies have suggested that reactive oxygen species play a major pathological role. Oxidative stress reduction induced by flavonoids has been regarded by many as the most likely mechanism in the protective effects of these compounds; however, there is an emerging view that flavonoids may also exert modulatory actions on protein kinase and lipid kinase signaling pathways. Quercetin, a major flavonoid present in the human diet, has been widely studied, and its biological properties are consistent with its protective role in the cardiovascular system. However, it remains unknown whether the cardioprotective effects of quercetin may also occur through the modulation of genes involved in cell survival. The main goal of this study was to examine the gene expression profiling of cultured rat primary cardiomyocytes treated with quercetin using DNA microarrays and to relate these data to functional effects. Results showed distinct temporal changes in gene expression induced by quercetin and a strong upregulation of phase 2 enzymes, highlighting quercetin ability to act also with an indirect antioxidant mechanism.

Deletion of serine 63 from P0 glycoprotein (P0S63del) causes Charcot-Marie-Tooth 1B neuropathy in humans, and P0S63del produces a similar demyelinating neuropathy in transgenic mice. P0S63del is retained in the endoplasmic reticulum and fails to be incorporated into myelin. Here we report that P0S63del is misfolded and Schwann cells mount a consequential canonical unfolded protein response (UPR), including expression of the transcription factor CHOP, previously associated with apoptosis in ER-stressed cells. UPR activation and CHOP expression respond dynamically to P0S63del levels and are reversible but are associated with only limited apoptosis of Schwann cells. Nonetheless, Chop ablation in S63del mice completely rescues their motor deficit and reduces active demyelination 2-fold. This indicates that signaling through the CHOP arm of the UPR provokes demyelination in inherited neuropathy. S63del mice also provide an opportunity to explore how cells can dysfunction yet survive in prolonged ER stress-important for neurodegeneration related to misfolded proteins.

Since any significant modification in the Se status, leading to changes in the activity of the seleno-enzymes, may have important consequences on the susceptibility of tissues to oxidative stress, considerable efforts have been made upon increasing Se dietary intake. In this respect, an important debate is still open about the bioavailability and the effectiveness of Se, and more generally nutrients, in supplements compared with foods. Using male Wistar rats, we have compared the effectiveness of two different diets in which an adequate Se content (0.1 mg/kg) was achieved by adding the element as sodium selenite or as component of a lyophilized Se-enriched food, in the counteraction of an oxidative stress induced by intraperitoneal administration of adriamycin. Both Se-enriched diets were able to reduce the consequences of the oxidative stress in liver, mainly by increasing glutathione peroxidase activity. This increase was more evident in rats fed on the diet enriched with the lyophilized food, probably due to the different chemical forms of Se, or to other components of the food itself. Although further studies are needed, data herein presented may contribute to the characterization of the effectiveness of Se from different sources, foods or supplements, in the light of dietary advice to the population concerning improvement of Se intake.

Clusterin is a protein involved in multiple biological events, including neuronal cytoprotection, membrane recycling and regulation of complement-mediated membrane attack after injury. We investigated the effect of recombinant human clusterin in preclinical models of peripheral neuropathies. Daily treatment with clusterin accelerated the recovery of nerve motor evoked potential parameters after sciatic nerve injury. Prophylactic or therapeutic treatment of experimental autoimmune neuritis rats with clusterin also accelerated the rate of recovery from the disease, associated with remyelination of demyelinated nerve fibers. These data demonstrate that clusterin is capable of ameliorating clinical, neurophysiological and pathological signs in models of peripheral neuropathies.

Axonal loss causes disabling and permanent deficits in many peripheral neuropathies, and may result from inefficient nerve regeneration due to a defective relationship between Schwann cells, axons and the extracellular matrix. These interactions are mediated by surface receptors and transduced by cytoskeletal molecules. We investigated whether peripheral nerve regeneration is perturbed in mice that lack glial fibrillary acidic protein (GFAP), a Schwann-cell-specific cytoskeleton constituent upregulated after damage. Peripheral nerves develop and function normally in GFAP-null mice. However, axonal regeneration after damage was delayed. Mutant Schwann cells maintained the ability to dedifferentiate but showed defective proliferation, a key event for successful nerve regeneration. We also showed that GFAP and the other Schwann-cell-intermediate filament vimentin physically interact in two distinct signaling pathways involved in proliferation and nerve regeneration. GFAP binds integrin alphavbeta8, which initiates mitotic signals soon after damage by interacting with fibrin. Consistently, ERK phosphorylation was reduced in crushed GFAP-null nerves. Vimentin instead binds integrin alpha5beta1, which regulates proliferation and differentiation later in regeneration, and may compensate for the absence of GFAP in mutant mice. GFAP might contribute to form macro-complexes to initiate mitogenic and differentiating signaling for efficient nerve regeneration.

Many reports indicate that dietary selenium, potentially increasing the activity of glutathione peroxidase, could offer protection against free-radical-induced damage. The effects of diets moderately enriched in selenium, as sodium selenite or as a lyophilized selenium-rich food, were studied in rats. Adriamycin, an anticancer drug causing a free-radical-mediated cardiotoxicity, was administered intraperitoneally to some rats. The onset of an oxidative damage was indicated by the increase in the plasma level of reactive oxygen metabolites coupled to a decrease in the total antioxidant activity but without modification of glutathione peroxidase activity, which were observed in all rats, independent of the dietary treatment. On the contrary, in the heart, selenium supplementation caused an increase in the total antioxidant activity, glutathione concentration, and glutathione peroxidase and catalase activities leading to a decreased generation of reactive oxygen metabolites. These results clearly indicate that a moderate Se dietary supplementation counteracts adriamycin-induced cardiotoxicity by preservation of endogenous antioxidants.

Mutations in MTMR2, the myotubularin-related 2 gene, cause autosomal recessive Charcot-Marie-Tooth type 4B1 (CMT4B1). This disorder is characterized by childhood onset of weakness and sensory loss, severely decreased nerve conduction velocity, demyelination in the nerve with myelin outfoldings, and severe functional impairment of affected patients, mainly resulting from loss of myelinated fibers in the nerve. We recently generated Mtmr2-null(neo) mice, which show a dysmyelinating neuropathy with myelin outfoldings, thus reproducing human CMT4B1. Mtmr2 is detected in both Schwann cells and neurons, in which it interacts with discs large 1/synapse-associated protein 97 and neurofilament light chain, respectively. Here, we specifically ablated Mtmr2 in either Schwann cells or motor neurons. Disruption of Mtmr2 in Schwann cells produced a dysmyelinating phenotype very similar to that of the Mtmr2-null(neo) mouse. Disruption of Mtmr2 in motor neurons does not provoke myelin outfoldings nor axonal defects. We propose that loss of Mtmr2 in Schwann cells, but not in motor neurons, is both sufficient and necessary to cause CMT4B1 neuropathy. Thus, therapeutical approaches might be designed in the future to specifically deliver the Mtmr2 phospholipid phosphatase to Schwann cells in affected nerves.

Osteoid osteoma is a small benign tumor that requires treatment due to the intense pain it causes. Surgical therapy has been the ablative technique of choice after a failure of medical therapy. Recently, numerous less invasive, alternative procedures have been proposed: drill trepanation with or without ethanol injections, cryoablation, and thermoablation with laser or radiofrequency. The aim of this review is to retrospectively assess the effect of radiofrequency (RF) thermoablation in the treatment of primary non-spinal osteoid osteoma. From June 2001 to July 2003, we treated 106 patients affected by osteoid osteoma with RF thermoablation. Five patients with spinal osteoid osteoma and four with a previously treated osteoma were excluded from the study. In this paper, we assess the results obtained in a selected group of 97 primary non-spinal osteoid osteoma. The lesions were predominantly in the metaphysics of the femur. Central nidus calcifications were frequent and there was no prevalence for which side they occurred. Primary success was achieved in 82 patients (85%), while we obtained secondary success in 15 patients (15%). In two patients (2%), pain persisted between the two treatments and failed to be resolved, even after the second treatment; therefore, surgical excision was performed and complete resolution was obtained. No complications were reported. In conclusion, our results confirm that the treatment of choice for non-spinal osteoid osteoma is RF thermoablation, offering several advantages over ablative techniques.

Osteoid osteoma is a small benign tumor, with a ''nidus'' that rarely exceeds 15 mm in diameter. It is relatively common in males, especially teenagers and young adults. It involves mainly the appendicular skeleton, the femur in particular, and rarely the axial skeleton. It requires treatment because it causes intense pain. In recent years alternative, less invasive, treatments have been proposed, such as drilling combined with ethanol injections, and thermal ablation with laser or radiofrequency. This study assesses 117 patients affected by osteoid osteoma, treated by radiofrequency thermal ablation between June 2001 and November 2003. We describe the patient recruitment procedure, CT-guided technique, the percutaneous approach, thermal ablation, and the instruments used. Data were analyzed thoroughly, and modifications that have improved the effects of treatment have been highlighted. The results achieved since the method was perfected have been extremely encouraging, confirming that the technique is very effective if performed correctly. For that reason radiofrequency thermal ablation has become the treatment of choice for non-spinal osteoid osteoma at Rizzoli Orthopaedic Institute.

Background: Many patients with established hypertension have poorly controlled blood pressure (BP). We studied demographic and clinical characteristics related to hypertension and analyzed the relationships between BP control and comorbidity., Methods: This study was based on 414 consecutive hypertensive out-patients referred to our nephrology clinic. We recorded systolic and diastolic BP, age, gender, body mass index, total cholesterol, family history of hypertension, glomerular filtration rate (GFR), 24-hr proteinuria, diabetes, coronary artery disease, smoking habits and antihypertensive drug treatment. BP control was considered optimal if BP was < 130/80 mmHg in patients with diabetes or chronic kidney disease (CKD), if BP was < 125/75 mmHg in CKD with proteinuria > 1 g/24 hr and if BP was < 140/90 mmHg in patients with no comorbidity. Multivariate logistic regression analysis was used to investigate the association between BP control and predictors., Results: Only 26.6% of patients had adequately controlled BP. Eighty-five percent of patients aged > 65 yrs had uncontrolled systolic hypertension. Univariate analysis showed a significant association between poor BP control and age >65 yrs, family history of hypertension, diabetes, CKD with or without proteinuria > 1 g/24 hr and total cholesterol > 220 mg/dL. Multivariate logistic regression showed that age > 65 yrs, diabetes and CKD with or without proteinuria > 1 g/24 hr were significantly and independently associated with poor BP control., Conclusions: Inadequate hypertension control is a common cause for referral to our out-patient nephrology clinic. Our data confirm that elderly patients, diabetic patients and nephropathic patients are difficult to treat; and therefore, deserve the highest quality clinical attention.

The authors propose a preoperative evaluation protocol for cases of dislocation of the prosthetic cup complicated by intrapelvic migration, obtained by studying 20 cases of prosthetic loosening with protrusion of the acetabular component in the pelvis, treated by reimplantation or explantation. In all of the patients, accurate preoperative planning was carried out, because of the considerable frequency of dislocation, compression or damage to the vascular and nervous structures deriving from migration inside the pelvis of the acetabular component. The authors suggest that in all cases of acetabular loosening evaluation involve standard X-rays, bone scan with technethium99 and with marked granulocytes, CT scan. When the cup protrudes in the pelvis, prior to surgery, CT scan with contrast medium will be required, and if the risk of vascular involvement exists, angiography should also be carried out.

Background: The risks connected with dialysis fluid contamination are well established. Epidemiological studies have demonstrated just how difficult it is to obtain permanently satisfactory quality standards. Therefore, dialysis centers must have effective and regular quality control programs, particularly with the growing and widespread use of online convective dialysis treatments. Considering this, we conducted a national survey of water treatment systems and monitoring in Italian dialysis centers., Methods: Two independent questionnaires were prepared and distributed in 1999 and 2001. The questions were designed to acquire information on structural and procedural elements. Responses to similar questions from both questionnaires were analyzed together., Results: Responses to questionnaires were received from 148 centers (17% of dialysis centers in Italy). In accordance with the European Best Practice Guidelines (EBPG) published recently concerning dialysis fluid purity, in the majority of centers (97%) the water treatment system consisted of at least pre-treatment and reverse osmosis (RO) modules. However, only one stage RO module was implemented (71%), there was a water storage tank (65%) and water pipe distribution loop was made of sanitary polyvinyl chloride (85%). Analysis of procedural elements--the timing and type of disinfection procedures used for the waterline system and monitors, the timing and type of water treatment quality control procedures--revealed a striking variability among centers in terms of the types and frequency of checks performed., Conclusions: Taking into account the EBPG, this survey revealed both bright and dark spots, calling for a national initiative aimed at defining a standard periodicity of loop disinfection, points in the water pipe line to be tested, and the frequency and type of tests.

In hemodialysis patients, oxidative stress results from an imbalance between the production of reactive oxygen species and antioxidant defense mechanisms. Recently, a new dialysis multi-layer membrane has been developed, by modifying the inner surface of regenerated cellulose to support a vitamin E coating. The aim of our study was to investigate the effects of hemodialysis treatment with vitamin E-modified membrane on anemia and erythropoietin requirement in a group of chronic uremic patients. Ten uremic, non diabetic, patients on standard bicarbonate dialysis were treated with vitamin E-bonded dialysis membrane for 12 months. Hematological parameters, erythropoietin requirement, serum vitamin E and serum malonyldialdehyde (MDA) were evaluated before starting the study and monthly. No significant changes in hemoglobin level, RBC count, hematocrit and EPO requirement were observed. Basal vitamin E levels were in the normal range (13.0 +/- 2.88 mg/L vs. 14.79 +/- 3.12 mg/L; NS). On the contrary, basal MDA levels were higher than those observed in the control group (1.87 +/- 0.36 vs. 1.13 +/- 0.18 mmol/mL; p < 0.01) and a significant decrease of MDA levels was found after 1 month of Excebrane treatment (1.39 +/- 0.25 nmol/mL; p < 0.02). In conclusion, the role of the "oxidative hemolysis" in the pathogenesis of anemia in CHD patients is still not clearly defined, but it could be of minor clinical relevance. Although the effectiveness of vitamin E-coated membranes as a scavenger of ROS allows a better control of intradialytic oxidative stress, it doesn't seem to contribute to clinical management of anemia in these patients.

The study involves a series of 10 primary neoplasms of the anterior cervical column (body and transverse processes) surgically treated by intralesional excision and followed-up after 2-10 years. The series included 6 benign and 4 malignant neoplasms. Among the benign tumors 4 cases were classified Enneking stage II (2 osteoid osteomas, 1 fibrous dysplasia, 1 osteoma): after simple excision none of the cases revealed symptoms or signs of recurrence at long-term follow-up. The other 2 benign forms were stage III (giant cell tumor and aneurysmal cyst): both of the cases were treated by extracapsular intralesional excision after selective arterial embolization and reconstruction with anterior fusion; the giant cell tumor was irradiated after surgery: at long-term follow-up the patients were asymptomatic and there were no signs of recurrence. The 4 malignant neoplasms (stage IIB) were 1 osteosarcoma and 3 solitary plasmacytomas with spinal cord compression. The osteosarcoma was treated by intralesional excision in 3 stages and radiation therapy, and there were no signs of disease 6 years after diagnosis. The cases of plasmocytoma were treated by intralesional excision and spinal cord decompression, anterior fusion with iliac graft and plate, radiation therapy, and chemotherapy, and they died after 2, 3 and 4 years with findings of multiple myeloma with no signs of disease at the level of the cervical vertebra treated.

With the purpose of clarifying the limits of resection surgery (en bloc excision) for the treatment of bone tumors of the spine, the authors report the indications and results of 43 operations. This series was homogeneous in terms of oncological and surgical staging, as well as with regard to surgical method used and anaesthesiology. Three different types of surgery were performed: en bloc resection of tumors of the body (sectors 5-9 or 4-8 depending on the WBB staging system), of the posterior arch (sectors 10-3) or characterized by eccentric growth (sectors 2-5 or 8-11). The surgical margins were histologically studied in all of the cases: based on the evaluation and on histological diagnosis further chemo- and/or radiation therapy were decided on. Long-term follow-up was obtained for all of the cases (from 6 to 153 months, mean 30 months; 26 cases followed for more than 24 months). Six of the patients died as a result of the disease from 10 to 28 months after resection. There were 4 local recurrences, 4 pulmonary metastases, and 5 metastatic disseminations to the skeleton and to other tissues observed in 11 patients. At final follow-up 33 patients (77%) were thus disease-free (32 continually), in excellent condition, and capable of living a normal life. Complications and treatment are also reported. A careful study of the neoplasm, an appropriate selection of the patients based on diagnosis and histological staging, a knowledge of the natural progression of bone neoplasms and of the surgical anatomy of the vertebral column, the application of suitable measures of anaesthesiological control, allow for a correct cost/benefit evaluation of this type of surgery as compared to oncological methods that are less effective but more diffused. On the basis of these considerations indications for en bloc resection in tumors of the spine are defined.

The study reports a series of 37 traumatic lesions of the cervical spine treated surgically by anterior approach. The series includes two IInd type fractures of the odontoid, treated by direct screwing, 32 recent fractures or fracture-dislocations of the lower cervical spine treated by decompression and anterior arthrodesis with a plate, 3 inveterate dislocations treated by anterior-posterior osteotomy in 2 cases, and decompression-arthrodesis in the third. One amyelic fracture of the odontoid healed in 4 months, the other patient, with Frankel C spinal cord lesion improved to D, but died 4 months later as a result of bronchial pneumonia ab ingestis. In all of the recent lower cervical lesions fusion was obtained in 3-12 months (mean 4.5 months). Eight incomplete spinal cord lesions improved by 2 Frankel classes in 3 cases and by 1 in 5. Six nerve root lesions healed with complete recovery. Three cases with no neurologic deficit remained unchanged as did 15 complete spinal cord lesions. In the 3 inveterate cases we obtained healing of a slow-developing myelopathy (Frankel D) after osteotomy, no improvement after osteotomy in the second case (Frankel B). In the case submitted to decompression and anterior fusion we obtained recovery from Frankel B to E in three months, but the patient then died as a result of pulmonary complications. Direct screwing of the odontoid allows us to obtain healing of the type II fractures without blocking C1-C2 movement with a posterior fusion. Anterior surgery in traumas of the lower cervical spine allows for anatomical decompression of the spinal cord and bone reconstruction with good results, avoiding the risk of neurologic progression caused by dragging of the disc material in the spinal canal, that may take place at the time of non-surgical reduction or by posterior approach of the dislocations. In our series complications included 2 infections, 1 that healed without sequelae and the other with kyphosis, and a fistula of the hypopharynx caused by fibrobronchoscopy 1 year after osteosynthesis, that healed after primary repair. For this latter complication anterior surgery can, at most, be considered a contributing cause, because of the deep scar.

Liposarcomas are one of the most common soft tissue malignant tumors; they can be differentiated in four histologic subtypes: well-differentiated, myxoid, round cell and pleomorphic liposarcomas. The search of differential CT and MR patterns to better classify the lesions in the proper histologic subtype is justified by the different histologic features, clinical course and especially prognosis, of every lesion subtype. From 1990 to 1995, 50 liposarcoma patients were examined preoperatively with CT and MRI in our Institute of Radiology. We found 7 well-differentiated liposarcomas (14%), twenty myxoid liposarcomas (40%), ten round cell liposarcomas (20%) and, finally, 13 pleomorphic liposarcomas (26%). The thigh was the most common tumor site (60%). The following parameters were considered: lesion margins, tissue homogeneity, fat tissue ratio and the presence of calcifications. Well-differentiated liposarcomas presented well-defined and regular margins (72%), mildly heterogeneous appearance (44%) and more than 75% fat tissue (72%). Myxoid liposarcomas presented well-defined and regular margins (65%), heterogeneous appearance (65%) and less than 25% fat tissue (95%). The diagnosis of myxoid liposarcoma can be made in the presence of myxoid tissue, which has very low CT attenuation values and mildly hypointense signal on T1-weighted and progressively hyperintense signal on T2-weighted MR images. Round cell and pleomorphic liposarcomas are high-grade malignancies and they cannot be distinguished from other malignant soft tissue lesions. In these cases, the diagnosis can be made only at histology.

Study Design: Twenty-nine patients with primary bone tumors and solitary metastases of the thoracolumbar spine treated with en bloc resection are reviewed retrospectively., Objective: To demonstrate the possibility to apply in the spine the same principles of surgical oncology adopted for primary bone tumors of the limbs., Summary of Background Data: The surgical oncologic staging systems currently applied in limb tumor surgery are difficult to apply to spinal tumors. The anatomic conditions make extralesional surgery difficult or impossible, which has restrained a more common use of resection surgery in the spine. Focus is put on a new surgical staging system and en bloc vertebral resection., Methods: Twenty-five primary malignant and aggressive benign bone tumors and four solitary metastases were treated. The patients were submitted to oncologic and surgical staging for surgical planning. The primary tumors were classified according to Enneking system: three Stage IA, six Stage IB, eight Stage IIB, eight Stage 3 benign. Staging according to the Weinstein-Boriani-Biagini system was also done. Thirteen lesions involved the vertebral body; nine lesions developed in the posterior arch, or part of it, and seven lesions occupied part of the body and part of the arch. A careful anesthesiologic evaluation was performed as well as a continuous intraoperative on-line monitoring of the vital parameters. The en bloc resections (multisegmental in five patients) were performed in 10 thoracic, in 16 lumbar, in two thoracolumbar lesions, and in one lumbosacral lesion. Reconstruction was performed, aiming to replace the resected columns. The specimens were submitted to histologic study of the margins. All the patients were followed, and their status was defined on clinical and imaging studies., Results: In 20 patients, a wide margin was achieved, in eight a marginal margin, in one an intralesional margin. The margin was contaminated in seven patients. Surgical time was 3-21 hours (average, 12 hours). No patient died during surgery or from surgical complications. Three mechanical failures of the implants required additional surgery. One deep infection arose. The only neurologic problems observed were related to the nerve roots sectioned for oncologic purpose. No local recurrence was found at follow-up evaluation after 6-134 months (average, 30 months)., Conclusions: En bloc resection can be performed in selected tumors of the spine; the indication to such major surgery must be based on the oncologic stage, and the procedure must be carefully planned. For this purpose, the Weinstein-Boriani-Biagini system could be a helpful tool. Long-term results must be weighed before a definitive statement of the indications can be made.

Study Design: A series of 10 patients surgically treated with prevascular or retrovascular extraoral retropharyngeal approach to the upper cervical spine is examined., Objectives: In orthopedic surgery, retropharyngeal approach may replace the transoral surgery, obviating the risks of infection and the uncomfortable postoperative course of cases in which median labiomandibular glossotomy was used to accomplish complex bone reconstruction., Summary of the Background Data: The transoral approach is reported in literature as the classical anterior access to the upper cervical spine that provides direct exposure for anterior decompression of the spinal cord. The risks, the surgical limits, and the postoperative difficulties of transmucosal access suggest the use of an anterior extraoral retropharyngeal approach in orthopedic surgery., Methods: The series includes four neoplastic lesions (osteoma, aneurismal bone cyst, giant cell tumor, solitary metastasis), three retropharyngeal ossifications resulting from diffuse idiopathic skeletal hyperostosis, and a single case of os odontoideum, craniocervical malformation, and postlaminectomy kyphosis., Results: At follow-up evaluation, all patients achieved a satisfactory outcome, with good clinical and radiographic results; nasotracheal intubation obviated the need for tracheostomy. The wide surgical exposure allowed reconstruction with iliac strut bone grafts and internal fixation in six patients, avoiding the need of a halo device. The only complications were four instances of transient palsies of the marginal mandibular branch of the facial nerve., Conclusions: In the anterior surgery of the upper cervical spine, the prevascular approach allows a wide surgical exposure, with visualization similar to that obtained with median labiomandibular glossotomy. The retrovascular approach is indicated in selected cases, such as tumor adjacent to the vertebral artery and C1-C2 arthrodesis with bilateral transarticular screws according to Barbour.

Cervical lesions caused by diffused idiopathic skeletal hyperostosis may cause compression of the upper respiratory and digestive paths. Horizontal anterior osteophytes that are not fused can cause dysphagia and dysphonia, large prevertebral ossifications extended or segmental may cause difficulty in breathing. A series of 6 cases with dysphagia, dysphonia, dyspnea due to duffused idiopathic skeletal hyperostosis, with cervical lesions is reported. In 3 cases, affected with moderate dysphagia, conservative treatment with anti-inflammatory drugs and a proper diet allowed for the symptoms to be controlled, and for spontaneous evolution of the lesions to occur, with fusion and remodeling of the compressive osteophytes. These patients continue to be asymptomatic 2-7 years after the first observation. In 3 cases affected with severe respiratory and/or nutrition deficit, the osteophytes and ossifications were surgically removed by prevascular extrapharyngeal approach, and rapid resolution of symptoms ensued. The follow-up 1-2 years after treatment showed that patients were asymptomatic and that radiographically there was no recurrence of lesions.

The authors describe the surgical anatomy of lateral approach to the upper cervical spine. The approach is retrovascular retropharyngeal extraoral allowing for anterolateral exposure of the upper cervical column, and it may be enlarged posteriorly on the homolateral posterior hemiarch of C1 and C2, and/or inferiorly on the lower cervical column. Absolute indications to this approach are anterolateral fusion with transarticular screws C1-C2 and excision of skeletal neoplasms adjacent to the vertebral artery. For other indications such as the treatment of anterior neoplasms and spinal cord decompression it is preferable to use pre-vascular extraoral approach or transoral approach.

Fractures of the occipital condyle are rare; 32 cases have been reported in the literature. Here, the authors describe four additional cases of occipital condylar fracture. Anderson's classification is used: type I fracture: comminution of the condyle without significant displacement; type II: basilar fracture extending into the condyle; type III: condylar avulsion. The possible mechanisms are identified. Computed tomography proved essential in diagnosing these fractures; coronal reconstructions together with axial scans are particularly helpful. Three-dimensional reconstruction did not prove essential in diagnosing these fractures.

We studied the anti-HCV prevalence in the same period in all the dialysis patients, staff members and blood donors of the same geographical area. In our opinion, the low prevalence (10.26%) in dialysis patients is strictly correlated to the low prevalence (0.46%) in blood donors.

Clinical usefulness of calcium acetate (CAA) as phosphorus binder was assessed in 19 stable hemodialysis patients with persistent hyperphosphatemia. All were dialysed thrice weekly with a constant dialytic schedule and a dialysate calcium of 3.5 mEq/l. One month prior the study beginning all patients stopped assumption of Ca and vitamin D supplements. In the first period of the study CAA (mean daily doses 2.2 g) was administered for one month followed by 15 days of withdrawal. The mean serum phosphorus decreased from 7.6 +/- 1.4 to 5.8 +/- 0.8 mg% (p < 0.005). After 15 days of withdrawal mean serum phosphorus reached the pretreatment value. Then the patients entered a long term study with personalized doses of CAA (between 1 and 4 g/day) and administration in 8 of them of alpha-calcidol. After a mean follow-up period of 5.4 +/- 1.5 months serum phosphorus was reduced from 7.5 +/- 1.1 to 5.6 +/- 1.1 mg% (p < 0.0005) while calcemia increased from 9.0 +/- 0.7 to 9.6 +/- 0.6 mg% (p < 0.005). Only one patient developed mild hypercalcemia. We concluded that CAA is a safe alternative to calcium carbonate for the control of hyperphosphatemia of uraemic patients for the most efficient phosphorus binding and the lesser absorption of calcium.

Recently, a proposal has been made to evaluate bone fragility in osteoporotic women by measuring ultrasound transmission velocity at the patella. Theoretically, sound transmission velocity depends on both bone mass and other factors which are not mass-dependent--e.g. bone architecture. Ultrasound transmission technique was thus tested for the capability of evaluating bone fragility factors, which are not mass-dependent, in the screening of osteoporotic women. To this purpose, the sound velocity at the patella of 31 healthy women was compared with that of 62 osteoporotic women with spontaneous vertebral fractures having similar bone mineral content. In 31 cases bone mineral content was similar to that of healthy women at the middle radius, and in 31 at the distal radius. Sound transmission velocity was significantly lower in osteoporotic than in healthy women. Fifty-two per cent of healthy women was correctly selected by US, relative to the risk threshold, versus 13% with bone mineral densitometry. This finding suggests that US is capable of distinguishing normal from osteoporotic women having similar bone mineral content, which means that non-mass-dependent factors may affect US velocity in the bone. Since the measurement were taken in various sites, different for US and bone densitometry, our results need confirmation in further studies where measurements are taken in the same sites.